From the end of trading last week to Friday's closing bell, the S&P 500 slid 2.7% -- its worst weekly performance since June 2012.

The volatile trading Friday came a day after a steep stock sell-off as financial markets went into a tailspin on Argentina's default on its debt, raising fears among skittish investors already fretting about corporate earnings growth, rising interest rates, global conflict and an aging bull market.

Investors Friday initially shrugged off a positive jobs report that showed employers added 209,000 jobs in July, the sixth straight monthly gain of more the 200,000.

Investors moved money into traditional safe havens: bonds and gold. The yield on the 10-year Treasury note fell to 2.5% from 2.55%. Gold rose 1% to $1,295 an ounce.

In addition to the 209,000 jobs added in July, the Labor Department said the unemployment rate bumped up slightly to 6.2% from 6.1% in June.

Asian stock markets also fell. but losses were limited by upbeat reports on China's economy. An official purchasing managers' index in China rose to its highest level in 27 months. A separate factory report by HSBC showed the strongest rate of improvement in a year and a half.